Breakfast – To eat or not to eat?

Is Breakfast Important?

Kirstie Lamb – Researcher and Trainer in Public Health/12 June 2017

Is breakfast the most important meal of the day?

It is a popular belief that ‘breakfast is the most important meal of the day’. Several studies have suggested that eating breakfast is associated with a reduced risk of gaining weight or being overweight and developing certain health problems, such as heart disease and diabetes [1, 2]. As such, three meals a day has become the traditional recommended frequency of eating. Despite this, many individuals still choose to skip breakfast and other research claims that this dietary decision may not actually be as bad as previously believed or may in fact offer health benefits [3].

As this is a widely debated subject, I will present the evidence for both consuming and skipping breakfast, highlighting the limitations of some studies. I will also provide recommendations for breakfast for those of you who wish to continue eating in the morning.

Why is breakfast recommended by some?

1. Eating breakfast reduces the likelihood of snacking, making bad food choices later in the day and weight gain.

It has been suggested that individuals who skip breakfast feel hungrier later in the morning. Making them more likely to snack (often on less healthy foods). Or overcompensate (eat more) at lunch and tea/dinner. However, despite a slight overcompensation of food at later meal times, many studies have failed to observe any effect on overall or daily calorie intake. And so weight is unlikely to be influenced negatively through this [4].

Recent clinical studies, where participants’ breakfast intake has been controlled, have shown no differences in body mass, body composition, overall daily energy intake or resting metabolic rate (the amount of energy your body needs to function at rest) when breakfast was eaten or skipped [5, 6]. Other studies have even shown the opposite, i.e. skipping breakfast reduced overall calorie intake [7, 8].

2. It gets our metabolism going in the morning and gives us energy to start the day.

This recommendation has been based on the belief that our metabolism slows down when we fast, leading to possible weight gain. However, recent clinical studies have indicated that this is not the case. Showing that metabolic rate does not differ after 6 weeks of fasting versus 6 weeks of consuming breakfast, in both lean and obese adults [5, 9]. Additionally, insulin levels decrease when we fast and therefore we are more likely to be in fat burning (rather than storage) mode. Meaning we can access more of our stored fat for the energy we need. Our body also releases other hormones, such as cortisol, to wake us up (increase our metabolism) in the morning without the help of breakfast!

3. Without it, we will have difficulty concentrating or performing tasks.

It has also been stated that eating breakfast improves our cognitive functioning. But these findings are inconsistent and also appear to vary between individuals. Some find skipping breakfast makes them feel lethargic whilst others are unaffected. The length of studies may also affect findings. If you are used to eating breakfast and then skip breakfast, you may experience difficulties in concentrating or be distracted by the feeling of hunger in the first couple of weeks. However, once you get used to skipping breakfast, it is likely that this will be resolved.

Why are there differences in opinion?

Studies vary in the way they are designed. For example, the populations examined, the amount of data collected or the length of the study. These factors lead to differences in opinion and make it difficult to work out which findings are correct. Additionally, these studies have many limitations which may help explain the discrepancies in conclusions, including:

Reasons for skipping have not been considered. One explanation is that, as some studies only take data from a single point in time, individuals who are overweight may in fact be skipping breakfast as a form of intermittent fasting to lose weight. By not recording or considering reasons for skipping, it is difficult to tell whether or not someone is overweight because of skipping breakfast, or if they are skipping breakfast because they are overweight.

Other lifestyle factors may have influenced findings. Individuals who choose to eat breakfast have also been observed to be more likely to be physically active, be non-smokers and to drink less alcohol [10]. Some studies have not taken physical activity and energy expenditure into account. All of these factors may have some influence on our health and it could be that, due to health promotion messages encouraging people to consume breakfast, healthy individuals are more likely to choose to eat breakfast i.e. it is not the consumption of breakfast directly making them healthier.

A correlation does not mean one thing causes another. Much of the evidence for associations between breakfast skipping and health measures is observational. This means that the researchers look back over large amounts of data to see if lifestyle factors and health markers correlate. Therefore, you cannot definitively say that a lifestyle decision directly causes a health problem (a correlation does not prove cause and effect). A good analogy for this is that just because the number of stalks happened to correlate with the number of babies born, this does not mean that one is the cause of the other, or that they are linked at all!

They have used self-reported data. Research often relies on self-reported dietary recall (i.e. ask people what they have eaten over the past week, month or year). This relies on people being able to remember and correctly recall what they have eaten, when they have eaten and how much (and relies on honesty!). Now I don’t know about you, but I personally would have difficulty accurately recalling what I have eaten over the last week, let alone in the last year!

There is a lack of consistency for the definition of ‘breakfast’. The definition used for ‘breakfast’ varies between studies, whilst some fail to define it at all! Some have just stated that any food or drink consumed within the morning counts as breakfast and therefore portion sizes or the types of food eaten are not taken into account; these are both factors that could influence weight gain, appetite and the development of health conditions.

Can skipping breakfast be good for my health?

Skipping breakfast may be associated with other health benefits, especially for insulin-resistant individuals. Skipping breakfast is often part of an intermittent fasting dietary approach; for example time-restricted eating where you only eat between certain hours of the day. This dietary approach has been linked to reductions in insulin levels (increasing potential time to use fat stores as a fuel source), improved insulin sensitivity, reduced inflammation and reduced risk factors for heart disease [11, 12]. Further clinical research is required to confirm these findings.

If you have any underlying medical conditions, take medication or are pregnant/trying to conceive, it is always recommended that you discuss any changes you wish to make to your diet with your doctor or health care team.

So does this mean that I shouldn’t be eating breakfast?

Not necessary. Just as skipping breakfast won’t directly influence your weight, eating breakfast won’t necessarily cause you to gain weight if you make sensible choices with the type and amount of food you eat at breakfast and at subsequent meals.

As always, one size does not fit all and so it is your choice whether or not you decide to eat breakfast – as long as it doesn’t negatively affect your health!

However, what is important is that you choose the right sort of food. For example, a lot of breakfast cereals, breads and spreads (e.g. chocolate spreads, jam and reduced fat spreads) are high in carbs and/or processed fats. They include added sugars and/or trans fats, despite many of these foods being advertised as healthy (see table 1 for carb contents of some typical breakfast foods). Breakfast cereals are made by processing and refining grains, reducing the nutritional value of the food as a result of removing vitamins, minerals and fibre. Although some cereals re-add these, the overall nutritional value is still arguably low. For people with a low carb tolerance, such as many individuals with prediabetes and diabetes, high or frequent intake of these cereals could have particularly serious effects on blood glucose levels and insulin resistance.

These cereals may also fail to provide a feeling of fullness or satiety, as consuming carbs leads to increased levels of insulin (causing the body to be in fat storage mode) and lower levels of the satiety (fullness) hormones leptin and PYY compared to eating protein or fat. This may actually result in you feeling hungrier at lunchtime, and/or consuming more food than you need later in the day, and/or gaining weight in the long term.

Table 1: Typical Breakfast Foods and Carb content

*other brands may vary slightly in carbohydrate content
**all carbohydrate impacts on blood glucose and insulin levels

Therefore, if you choose to eat breakfast, try to ensure that you are consuming good quality, protein-rich foods, such as eggs, as these will keep you feeling full for longer. Protein suppresses the release of a hunger hormone called ghrelin and therefore prevents you from feeling hungry. A protein-rich breakfast will have a less adverse effect on blood glucose levels. An alternative to eggs would be to have whole natural yoghurt along with berries and/or nuts. If you do choose to have cereal, watch your portion size. Make sure that you select a product that is fibre-rich, less-processed and does not have added sugar.

Concluding thoughts…

So, if you enjoy eating breakfast and would like to continue then do, but choose wisely! If you want to continue skipping breakfast, current evidence does not suggest that it will have adverse effects on your weight. It may in fact offer other health benefits. If you would like to try intermittent fasting by skipping breakfast***, be aware that the switch may take a couple of weeks to get used to, so hang on in there until your body adjusts!

Whichever you choose, ensure that you are making healthy choices for other foods consumed during the day and are following the most appropriate dietary approach for you and your health.

***if you are on blood glucose lowering medication, please check with your healthcare team first that this will not put you at risk of experiencing low blood glucose levels (hypoglycaemia)

References 1-10

1. Mekary, R.A., Giovannucci, E., Willett, W.C., van Dam, R.M. and Hu, F.B, Eating patterns and type 2 diabetes risk in men: breakfast omission, eating frequency, and snacking. Am J Clin Nutr, 2012. 95: p. 1182–9.

2. Deshmukh-Taskar, P., et al., The relationship of breakfast skipping and type of breakfast consumed with overweight/obesity, abdominal obesity, other cardiometabolic risk factors and the metabolic syndrome in young adults. The National Health and Nutrition Examination Survey (NHANES): 1999–2006. Public Health Nutrition, 2012. 16(11): p. 2073–2082.

3. Barr, S.I., L. DiFrancesco, and V.L. Fulgoni, Association of breakfast consumption with body mass index and prevalence of overweight/obesity in a nationally-representative survey of Canadian adults. Nutrition Journal, 2016. 15(1): p. 1-9.

4. Chowdhury, E.A., et al., Effect of extended morning fasting upon ad libitum lunch intake and associated metabolic and hormonal responses in obese adults. Int J Obes, 2016. 40(2): p. 305-311.

5. Chowdhury, E.A., et al., The causal role of breakfast in energy balance and health: a randomized controlled trial in obese adults. The American Journal of Clinical Nutrition, 2016.

6. Dhurandhar, E.J., et al., The effectiveness of breakfast recommendations on weight loss: a randomized controlled trial. Am J Clin Nutr, 2014. 100(2): p. 507-13.

7. Gonzalez, J.T., Veasey, R.C, Rumbold, P.L.S, and Stevenson, E.J., Breakfast and exercise contingently affect postprandial metabolism and energy balance in physically active males. British Journal of Nutrition, 2013. 110: p. 721-732.

8. D.A.Levitsky, C.R.P., Effect of Skipping Breakfast on Subsequent Energy Intake. Physiology and Behavior, 2013. 119: p. 9-16.

9. Betts, J., Richardson, J. D., Chowdhury, E., Holman, G. D., Tsintzas, K. and Thompson, D., The causal role of breakfast in energy balance and health:A randomized controlled trial in lean adults. The American Journal of Clinical Nutrition, 2014. 100(2): p. 539-547.

10. Keski-Rahkonen, A., Kaprio, J., Rissanen, A, Virkkunen, M and Rose, R.J., Breakfast skipping and health-compromising behaviors in adolescents and adults. European Journal of Clinical Nutrition, 2003. 57: p. 842–853.

References 11-12

11. Barnosky, A.R., et al., Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings. Transl Res, 2014. 164(4): p. 302-11.

12. Tinsley, G.M. and P.M. La Bounty, Effects of intermittent fasting on body composition and clinical health markers in humans. Nutr Rev, 2015.